Cellular immune responses in the skin of sheep infected with larvae of Lucilia cuprina, the sheep blowfly.

Cellular immune responses were observed in the skin of sheep after primary and secondary infection with sheep blowfly (Lucilia cuprina) larvae. Both primary and secondary infections resulted in a massive cellular infiltration within 48 h of wound initiation, with the majority of cells having the CD45 phenotype. Neutrophils comprised the major cell type at the skin surface. In the dermis, the number of CD4+ T helper, gamma delta-TCR+ cells and T19+ (CD4-, CD8-) T cells also increased significantly in skin during both primary and secondary infections compared with control sites. However, there was no significant difference in the numbers of these cells between primary and secondary infections. An increase in the expression of the CD1 antigen on Langerhans/dendritic cells was observed, along with an apparent increase in the number of these cells in secondary lesions, with the majority of the cells being concentrated in the upper dermis and epidermis. While there was no increase in mast cells, eosinophils increased significantly during infection compared with control sites. The cellular infiltration observed following primary and secondary infections suggests polyclonal activation of T cells and their selective recruitment to the lesion site.     

Tablet computers in the veterinary curriculum

Tablet computers offer a new method of information management in veterinary medical education. With the tablet computer, students can annotate class notes using electronic ink, search for keywords, and convert handwriting to text as needed. Additional electronic learning resources, such as medical dictionaries and electronic textbooks, can be readily available. Eleven first-year veterinary students purchased tablet computers and participated in an investigation of their working methods and perceptions of the tablet computer as an educational tool. Most students found the technology useful. The small size and portability of the tablet allowed easy transport and use in a variety of environments. Most students adapted to electronic notetaking by the second week of classes; negative experiences with the tablet centered on a failure to become comfortable with taking notes and navigating on the computer as opposed to writing and searching on paper. A few performance-related problems, including short battery life, were reported. Tablet software allowed conversion of faculty course notes from a variety of original formats, meaning that instructors could maintain their original methods of note preparation. Adopting a consistent naming convention for files helped students to locate the files on their computers, and smaller file sizes helped with computer performance. Collaboration between students was fostered by tablet use, which offers possibilities for future development of collaborative learning environments.     

Binding of mouse mannan-binding lectins to different bacterial pathogens of mice

Humans have one mannan-binding lectin (MBL) in circulation but rodents, pigs, rabbits and rhesus monkeys have two, MBL-A and MBL-C. Plasma forms of these proteins have similar mannan-binding activity in vitro, but might differ in their ability to bind other microbial targets. In these studies, we compared carbohydrate-dependent binding of mouse plasma MBL-A and MBL-C to mannan-sepharose beads and to intact bacteria isolated as pathogens from mice. After incubation of mouse plasma with intact bacteria, MBL-A and MBL-C were eluted with N-acetylglucosamine (GlcNAc) and identified in nonreducing SDS-PAGE using Western blot analysis and MBL-A or MBL-C specific monoclonal antibodies. GlcNAc eluates of plasma incubated with mannan-sepharose beads, Klebsiella oxytoca and Staphylococcus aureus contained similar bands (mainly approximately 50kDa) that were immunoreactive with MBL-C antibody. Furthermore, a smaller form of MBL-C (approximately 45kDa) was detected bound to Pseudomonas aeruginosa. By comparison, immunoreactive MBL-A (a ladder of approximately 175kDa and larger bands) was identified in these GlcNAc eluates from mannan-sepharose beads, S. aureus and K. oxytoca but not P. aeruginosa. These studies demonstrate that mouse MBL-A and MBL-C in plasma are not equivalent in their ability to recognize bacteria that are pathogens for mice.     

The inventory of carbon stock in New Zealand’s post-1989 planted forest for reporting under the Kyoto protocol

The United Nations Framework Convention on Climate Change (UNFCCC) requires reporting net carbon stock changes and anthropogenic greenhouse gas emissions, including those related to forests. This paper describes the design and implementation of a nation-wide forest inventory of New Zealand’s planted post-1989 forests that arose from Land Use, Land-Use Change and Forestry activities (LULUCF) under Article 3.3 of the Kyoto Protocol. The majority of these forests are planted with Pinus radiata, with the remainder made up of other species exotic to New Zealand. At the start of the project there was no on-going national forest inventory that could be used as a basis for calculating carbon stocks and meet Good Practice Guidelines.A network of ground-based permanent sample plots was installed with airborne LiDAR (Light Detection and Ranging) for double sampling using regression estimators to predict carbon in each of the four carbon pools of above- and below-ground live biomass, dead wood and litter. Measurement, data acquisition and quality assurance/control protocols were developed specifically for the inventory, carried out in 2007 and 2008. Plots were located at the intersection of a forest with a 4 km square grid, coincident with an equivalent 8 km square grid established over the indigenous forest and “grassland with woody biomass” (Other Wooded Land). Planted tree carbon within a ground plot was calculated by an integrated system of growth, wood density and compartment allocation models utilising the data from measurements of trees and shrubs on the plots. This system, called the Forest Carbon Predictor, predicts past and future carbon in a stand and is conditioned so that the calculated basal area and mean top height equals that obtained by conventional mensuration methods at the time of the plot measurement. Mean per hectare carbon stocks were then multiplied by an estimate of the total area of post 1989 forests obtained from wall to wall mapping using a combination of satellite imagery and ortho-photography.The network of permanent samples plots and LiDAR double sampling methodology was designed to be simple and robust to change over time. In the future, using LiDAR should achieve sampling efficiencies over using ground plots alone and reduces any problems regarding restricted access on the ground. The network is to be remeasured at the end of commitment period 1, 2012, and the carbon stocks re-estimated in order to calculate change.     

The immune response of sheep infected with larvae of the sheep blowfly Lucilia cuprina monitored via efferent lymph

Changes in lymphocyte traffic in efferent lymph from the prescapular lymph node of sheep were monitored during local primary and secondary infection with blowfly, Lucilia cuprina. During primary infections the response was characterised by an increase in the output of CD4⁺ T cells over CD8⁺ T cells for the first 48 h after wound initiation. By 72 h the output of CD8⁺ T cells exceeded that of CD4⁺ T cells. During secondary infections the increased output of CD8⁺ T cells was more pronounced and occurred earlier at approximately 48 h. The percentage of B lymphocytes as measured by sIg, CD45R and MHC class II expression increased at approximately 96–120 h after both primary and secondary infections, with the secondary response being greater than the primary. This increase in B cells corresponded with peak antibody titres recorded in the efferent lymph to a first instar antigen preparation as measured by ELISA. An increase in IFN-γ and soluble IL-2 receptor was recorded after both primary and secondary infections, with the response after secondary infection being greater than that recorded after primary larval infections.     

Coupled 186Os and 187Os evidence for core-mantle interaction

Osmium isotopic analyses of picritic lavas from Hawaii show enrichments in the osmium-186/osmium-188 ratio (186Os/188Os) of 0. 008 to 0.018%, relative to a chondritic upper mantle, that are positively correlated with enrichments in 187Os/188Os of 5.4 to 9.0%. The most viable mechanism to produce these coupled 186Os and 187Os enrichments is by addition of 0.5 to 1 weight percent of outer core metal to a portion of the D" layer and subsequent upwelling of the mixture. These data suggest that some plumes originate at the core-mantle boundary and that Os isotopes may be used to distinguish plumes derived from shallow versus deep mantle sources.     

Evaluating habitat associations of a fish assemblage at multiple spatial scales in a minimally disturbed stream using low‐cost remote sensing

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